Stabilized diazx-type  sensitive



Patented July 18, 1944 UNITED STATES PATENT OFFICE STABILIZEDDIAZO-TYPE- SEN SITIVE MATERIAL No Drawing.

Application December 4, 1942,

Serial No. 467,901

11 Claims.

This invention relates to the stabilization ol light-sensitive layerswhich are produced by the incor ration or a dlazo compound as the llghusensitive medium onto the surlac 0! a suitable carrier base. Moreparticularly. it refers to the stabilization of so-called drydevelopment or two component dlazo type lightscnsitivc layers whereinthe diazo compound is 0. disco compound derived from ortho or paraaminonaphthol or from N-mono or di-substltuted aromatic persdiaminessuch 8.5 para amino aniline compounds, which diazo compound isincorporated into the light-sensitive layer. together with an azo dycstufi coupling component.

Various processes are known for the preparation of light-sensitivelayers which depend upon the use of a diazo compound as thellght-sensltive medium, and various materials have been employed for thecarrier of the light-sensitive layer, including textiles, paper,celluloslc films, and glass and metal surfaces. The sensitized carrieris exposed to light under a transparent original which it is desired toreproduce and the disco compound is decomposed in th areas unprotectedby the outline of the original. The undecomposed diazo compound in theprotected areas is then used to develop the image or the original bycoupling the said dlazo compound in alkaline atmosphere with an emdyestufl coupling component. In the two component layers whichcontemplate the incorporation of the coupling component into thelight-sensitive layer with the dlszo compound, the develo ment or thedyestufl iorming the image i flected by brin ing the exposedlight-sensitive layer into contact with ammonia gas. This is known asthe dry developing process.

The dyestufl components, as applied on the carrier, are relativelyunstable and cannot be stored for long periods prior to use.

The light-sensitive layers which carry the coupling component as well asthe dlazo compound in the light-sensitive layer are subject to prematurecoupling of the said dyestufl components as well as decomposition of thedlazo compound upon long storage. Many attempts have been made to obtainmore stable coating solutions and to render the light-sensitive layersproduced therefrom less sensitive to deterioration without impairin thelight-sensitive qualities oi the diazo compound upon which theproduction 01' accurate images from the original depends. These attemptshave hitherto been relatively unsuccess- Iul. It is therefore the objectof this invention to provide coating solutions and light-sensitive itcoon wherein R stands for a radical of the group consisting of alkyl.phenyl, pyridyl, quinolyl, and

substituted phenyl. pyridyl and qulnolyl radicals. Examples oi suchcompounds are:

Crotonic acid CHJCH=CHCOOH Pentenic acid CsHsCH=CHCOOH Sulio-cinnsmicacid CB=CHCOOU soul Betai alpha-pyridyl) -acrylic acid N CH==CH-COORBeta-Z-methyl-quinolyl (5) -acryllc acid noocnc==cn The compounds ofthis group can exist in both the cisand transform, either of which issuitable for the purposes oi this invention. Diazotype light-sensitivelayers which have been stabilized by addition or compounds selected fromthe above group show greatly improved keeping qualitles and are stableagainst decomposition or deterioration ior much longer periods ofstorage than has been possible with the same dlazo lightsensitivecompositions lacking this stabilizing ii'ibound ii'n which previouslySUgEELLEd sta- 50 cc. isopropanol are added. The stability of billzingcompounds have been used. The ioiiow the coating made according to thisexample was ing examples illustrate the invention but they found to besuperior to that of a comparison coatui'e not intended to limit itthereto. The pa t irig made from a similar coating solution but conareby weight unless otherwise stated. taining no acrylic acid stabilizer.

g xqnip I. ample Vt 2-1-diazo -hydroxy-rihi h hillEIfQ-iJ-BUUDIHC" Partsa id prirts 14.0 Zinc chloride double salt or the diazo-com- Conc.hydrochloric acid -i0 pound obtained from N-cthanol-ethyl parts by v9 wn 1 i7 0, ammo qq i gql 10.5 Nickel sulphate ;-1 m't.; its. Qitric 50Pmorogiucine -do 4.9 2-Q-dihydroxy-naphthalene 5.0 Thiourea -22 lLliLsdox- 20.0? 'LhibQieaL-Q UIs't z'ME- 45 .i-Jl I il u 1! Cl NB] U Lwere dissolved in 1000 cc. 0! v ste r. Befor t r} fiiifi jg gfiigfti:fff f i f 6 32 5 ing there were added 8.74 grams per liter ofcro-Mfmmqmmgmwkpmw 0 6.9

tonic acid. This solution wts tnerr-apieqgt, paper, fabric, film or thelike by the usual coat ivere'dissoived in 1000 cc. oi water. Beforecoating method, using a doctor blade to insure srgthlrt. ,llliliiherewere added 255 grams oi sulio-cinnilmic even coating. Alter storage atroom temperature acid. This solutlon was spread on a suitable peso.sevfal: months imasmmmy i mig mze such as paperfiidbriciflin'i orthe'lil'r'e: by the usual material cont-aiding the' drotonic acid wastiesbcd coatir fl it hod lll't'il 'saine marit er s iti'diesteqbyexposing lde'st' piebe to-ilght Under-a suitable -in'-Fi1xam'ple'12"The"1igliU BBIiSiLMKE-Ipij h thus dlupositive and deveicpirrgthe-ima e by appli prouuceti was thetist orefd ailroomjtriiperatri'rerbr eation or ammonia'gasf 'lh'e resliltlri image fro- 26'severai rn'onths ahdits stsbiiltv t ei-iit'etdby produced ctr-thelightkseh'sltlve layer coht'aiznirig observin the ap eeriinee or" win; m'tii' 1 tig i w g m t u mgg sensitive'lbiye'r due to prematurecoupling'of'the r produce'd under thsamecondit ns 118W: ,P 'and'*bycdfiiba'ris'dii difi lihtsensltive'lflyer madeiroflfithsiflmimaterials out senaltlve qiis.iitieo mm those" 'of" si*t'es'tfsm;iicontaining-no--erot mic tteid 'wmen had-{been proparedah'dt'reatedirithtz'sanie satisfies mm titdred uhier mettle?cori'diti'onsflior the so me -iignt-seri sitive laser 5i 'thrs'i'tampie'butkiiriittirig lehgtho'! timei 1 Th bsck'grouiid'a'h'rioo'n'sequ'ent"- the sulio -cinnsi riivabld ad'dlti'o'h; It-lfia''{Qdti'q iy the contrast of the image reproduced on the thdtthe'liizhtslensitivelayersdiddeili sttiidifdfati'de iightsensltive layer made inaccordance with this with this example shovtiflr'ieg'liig'ifilia"arii'odnt. of example was superior to that of thesample which coloring due to refnh'tu're coppliii'g -ofithfi does notcontain th'croton'ic acid in the lightoompong it 5mg. ain'kh fly' ersrmiad'e sensitive l ve irom' theit'mjri seiutib'r'iiii'ilt'fhpt a i g; mg; "maps H m weete Wtbe c' fidrili Th p eiisthesamessinwmamnlo-rl sconsieeese 'anieairitoi siciini 'diiw rhia except that in place of thecrownic acid as a curco'upliiigi it' wii jiisd fmjfi flihe fitig 55stabilizer 10.0 grams or ente i acid per liter mt q ht iihder aiiitstii-siabbgit te fia are used. The stability 'or the qoqt in pa s deutmp mrimgq twg ,iinm g i amg w 4. w i a es fler id i rawji similarcoating solution but oontainingno acrylic 19 buckgro "fi n w m ri g t i't i ing to this example was ioundto be superior tostabilizer'fi'ilfflamd ol cioto'r'iic said'sei tei si that of acomparison coating made from a similar 55 usadi-fl rho starbilitroi thefcbit'tihiz'hihde iiccofd coating solution but containing no acrylic acidin]; w this exam'ple wsb' fbundwobiitifiiidito stabilizer. that of a.comparison coating mi'iciei'frorr igsif fllsr Example IV I 4 r naggingbolutlohitiut do'rimm{fig fl l yn kq The composition or the coatlpgsolution is the i r same as in mample I except that in place or thecrotonic acid as a stabilizer, 15.15 grams of betatalpha-pyridyl)acrylicacid per liter are exoe t that-jnr la r.is l nnam cii employed. Toiacilitqte solution cc. of alcohol muu nqo g gm m mi g. mg 81'! added tot h waterT,The stability of the COBta mecbq qfh wbunyi 6p i-PW. s w/teemiilisrwmle JYMJ RM w cording w thlsfhxh'rfrblE wsi gc imd'tai' s'e' s11has be u or. o l t-,9! A ome isen cmi z made to that ium esmsaiisaaethiti ii iiia yi is shoot-mi r. (Dhoisprocadure 11s .lthe 'samtr as inmehifawv rg tion 50 cc. of alcohol are added. The stability oi thecoating made according to this example was iound to be superior to thatoi a comparison coating made from a similar coating solution butcontaining no acrylic acid stabilizer.

Example X 2 methyl 4 amlnobenzene 9.8 Citric acid 50 Resorclne 6.5'Ihiourea 45 The sodium salt oi the naphthalene-1,3,6,

trisulionic acid 32,6 Aluminum sulfate are dissolved in 1000 cc. of

water 6.9

To this solution there are added 25.5 grams of suliocinnamic acid perliter. The coating. storage and testing procedures are the same as inExample I. The stability oi the coating made according to this examplewas iound to be superior to that of a coating made from a solution notcontaining an acrylic acid stabilizer.

Aluminum suliate are dissolved in 1000 cc. of

water To this solution there are added 255 grams of sulio-cinnamlc acidper liter. The solution is then spread on a suitable base, such aspaper, iabric, him or the like by the usual coating method in the samemanner as described in Example I. The light-sensitive layer thusproduced is then stored at room temperature ior several months, and itsstability is then tested by observing the appearance of color in thelight-sensitive layer due to decomposition of the dimcompound and bycomparison with that or a test sample prepared and treated in the samemanner as the light-sensitive layer of this example but omitting thesuiio-cinnamic acid. The test pieces are then exposed to light under asuitable diaposltlve and the images developed by application oi analkali solution of a suitable azo component such as phloroglucine,resorcine, or 2-3-dihydroxy-naphthalene. The resulting image produced onthe light-sensitive layer containing the sulio-cinnamic acid showed amuch higher color contrast of the image: indicating the prevention ofthe decomposition and the consequent discoloration of the disco-compoundwhile at storage under the some length or time.

Various changes may be made in the details oi my invention as describedin the foregoing specidcation within the scope of the claims appendedhereto without sacrificing the advantages oi myinvention.

I claim:

1. The process or increasing the stability 0! a diazotypelight-sensitive layer containing a suitable diazo compound whichcomprises adding to the coating solution on alpha-bcta-unsaturetedacrylic acid or the tollowing formula:

wherein it stands for a radical selected from the group consisting oiallryl, phenyl, pyridyl, quinolyl and substituted phenyl, pyridyl andquinolyl radicals. and coating is suitable base with said solution.

2. The process of increasing the stability of a dlazotypelight-sensitive layer containing a diazo compound suitable for iomiing astable two component diazotype layer and an am dye coupling component,which comprises adding to the coating solution an alpha-beta-Lmsaturatedacrylic acid of the following formula:

wherein R stands for a radical selected from the group consisting ofalkyl, phenyl, pyridyl. quinolyl and substituted phenyl, pyridyl andquin olyl radicals, and coating a suitable base with said solution.

3. The process of increasing the stability oi a diazotypelight-sensitive layer containing a diazo compound derived from a paraamino aniline compound and an azo dye coupling component, whichcomprises adding to the coating solution containing the said diazocompound an alphabeta-unsaturated acrylic acid or the following whereinR stands for a radical selected from a group consisting of alkyl,phenyl, pyridyl, quinolyl and substituted phony], pyridyl and quinolylradicals, and coating a suitable base with said solution.

4. The process oi increasing the stability of a diazotypelight-sensitive layer containing a diazo compound obtained from an orthoamino naphthol compound and an azo dye coupling component. whichcomprises adding crotonlc acid to the coating solution and coating asuitable base with said solution.

5. The process oi increasing the stability of a diazotypelight-sensitive layer containing a diam compound obtained from a paraamino aniline compound and an arc dye coupling component, whichcomprises adding sulfo-cinnamic acid to the coating solution and coatinga suitable base with said solution.

8. The process of increasing the stabilit at a diaz-otypelight-sensitive layer containing a diam compound obtained lrom a paraamino aniline compound and an azo dye coupling component, whichcomprises adding pentenic acid to the coating solution and coating asuitable base with said solution.

'7. Light-sensitive layers on a suitable base comprising a diazocompound suitable for forming a stable two component diazotype layer. anazo dyestufl coupling component and an alpha-betaunsaturaicd acrylicacid of the foilowma formulo:

wherein R stands for a. radical selected from the group consisting ofalkyl hony], pyridyl. quinoiyi and substituted henyi, pyridyi andquinolyi radicals 8. Light-sensitive layers on a suitable basecomprising n dinzo compound obtained from a para amino aniline compound.an azo dye coupling component. and an aipha-beta-unsaturated acrylicacid or the 'oiiowing iormuiat wherein R stands for a radical selectedfrom the group consisting or alkyl, phcnyl, pyridyl, quinclyi ondsubstituted phenyi, pyridyi and quinoiyl rsdioais.

9. Liam-sensitive layers on a suitable base com prising a diam-compoundobtained from an ortho amino naphthoi compound, an azo dye coupiinlcomponent and crotonic acid.

10. Liam-sensitive layers on a. suitable bue comprising a dim compoundobtained irom 4i para amino aniline compound, an azo dye couplingcomponent and sulio-cinnamic acid.

11. Light-sensitive layers on a suitable blue comprising a diazocompound obtained from a para amino aniline compound, an azo dyecoupiin: component and pentenic acid.

MAXINHLIAN K. REICHZEL

